//
//  UIImageView+CB_Extension.m
//  YJB
//
//  Created by YJB on 2016/11/3.
//  Copyright © 2016年 YJB. All rights reserved.
//

#import "UIImageView+CBExtension.h"

@implementation UIImageView (CBExtension)
-(void)cb_setQRCodeImageWithContent:(NSString *)content QRCodeImageSize:(CGFloat)size
{
    // 1.创建过滤器
    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
    
    // 2.恢复默认
    [filter setDefaults];
    
    // 3.给过滤器添加数据(正则表达式/账号和密码)
    NSString *dataString = content;
    NSData *data = [dataString dataUsingEncoding:NSUTF8StringEncoding];
    [filter setValue:data forKeyPath:@"inputMessage"];
    
    // 4.获取输出的二维码
    CIImage *outputImage = [filter outputImage];
    // CIImage类型转CGImage，再转image，这样能获的清晰的二维码
    CGRect extent = CGRectIntegral(outputImage.extent);
    CGFloat scale = MIN(size/CGRectGetWidth(extent), size/CGRectGetHeight(extent));
    
    // 1.创建bitmap;
    size_t width = CGRectGetWidth(extent) * scale;
    size_t height = CGRectGetHeight(extent) * scale;
    CGColorSpaceRef cs = CGColorSpaceCreateDeviceGray();
    CGContextRef bitmapRef = CGBitmapContextCreate(nil, width, height, 8, 0, cs, (CGBitmapInfo)kCGImageAlphaNone);
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef bitmapImage = [context createCGImage:outputImage fromRect:extent];
    CGContextSetInterpolationQuality(bitmapRef, kCGInterpolationNone);
    CGContextScaleCTM(bitmapRef, scale, scale);
    CGContextDrawImage(bitmapRef, extent, bitmapImage);
    
    // 2.保存bitmap到图片
    CGImageRef scaledImage = CGBitmapContextCreateImage(bitmapRef);
    CGContextRelease(bitmapRef);
    CGImageRelease(bitmapImage);
    self.image = [UIImage imageWithCGImage:scaledImage];
}

@end
